Polypterus senegalus, the Senegal bichir, gray bichir or Cuvier’s bichir, and sometimes called the «dinosaur eel» (a misnomer, as the creature, is neither an eel nor a dinosaur) also called «dinosaur bichir» or «dragon fish» is in the pet trade due to its lungfish-like appearance which was described as more primitive and prehistoric than other modern fishes. It is a prototypical species of fish in the genus Polypterus, meaning most of its features are held across the genus. Commonly kept in captivity by hobbyists. They are native from Africa where they are the most widespread species of the genus.
An elongated fish, usually grey or beige in colour, it sometimes has shades of white, pink or blue on some scales. Most of the fish is covered in very subtle patterns with occasional darker blotches or dots. The face is smooth and rounded at the nose with larger scales than the rest of the fish, external nostrils protrude from the front. Eyes are on each side of the head, they are usually pale yellow with a black pupil, the mouth is large and seems to grin when closed. The body is long and vaguely cylindrical, a serrated dorsal fin runs along most of the body until it meets the caudal fin which is pointed and flat. The pectoral fins attach just behind and below the gill openings, and are the primary means of locomotion, providing a slow, graceful appearance. P. senegalus is smaller than other bichirs, reaching about 35.5 cm (14 in).
The fish has a pair of primitive lungs instead of a swim bladder, allowing it to periodically gulp air from the surface of the water. In the aquarium, bichirs can be observed dashing to the surface for this purpose. This bichir’s skin serves as a particularly effective armor, and has been studied as a model for personal armor for better combinations of protection and mobility.
During active hours, Polypterus senegalus swim about their environment, performing activities such as exploring, feeding, hunting, investigating changes, and scavenging. Social behavior is also observed as P. senegalus sometimes follow each other moving about.
This species of bichir is found in lakes, river margins, swamps, and floodplains of tropical Africa and the Nile river system, it occurs in at least twenty-six African countries which include Senegal, Egypt, Democratic Republic of Congo, Cameroon, Chad, Ethiopia, Kenya, Mali, Ivory Coast, Tanzania, Sudan, Nigeria, Gambia, Uganda, and others. Its distribution is widespread, detailed to include the Nile basin and West Africa (Senegal, Gambia, Niger, Volta, and Lake Chad basins, and Congo River Basin.